Latitudinal differences in the amplitude of the OAE-2 carbon isotopic excursion: pCO2 and paleoproductivity
Elisabeth C. van Bentum
Jacobus S. Sinninghe Damsté
- A complete, well-preserved record of the Cenomanian/Turonian (C/T) Oceanic Anoxic Event 2 (OAE-2) was recovered from Demerara Rise in the southern North Atlantic Ocean (ODP site 1260). Across this interval, we determined changes in the stable carbon isotopic composition of sulfur-bound phytane (δ13Cphytane, a biomarker for photosynthetic algae. The δ13Cphytane record shows a positive excursion at the onset of the OAE-2 interval, with an unusually large amplitude (~7 ‰) compared to existing C/T proto-North Atlantic δ13Cphytane records (3–6 ‰). Overall, the amplitude of the excursion of δ13Cphytane decreases with latitude. Using reconstructed sea surface temperature (SST) gradients for the proto-North Atlantic, we investigated environmental factors influencing the latitudinal δ13Cphytane gradient. The observed gradient is best explained by high productivity at DSDP Site 367 and Tarfaya basin before OAE-2, which changed in overall high productivity throughout the proto-North Atlantic during OAE-2. During OAE-2, productivity at site 1260 and 603B was thus more comparable to the mid-latitude sites. Using these constraints as well as the SST and δ13Cphytane-records from Site 1260, we subsequently reconstructed pCO2 levels across the OAE-2 interval. Accordingly, pCO2 decreased from ca. 1750 to 900 ppm during OAE-2, consistent with enhanced organic matter burial resulting in lowering pCO2. Whereas the onset of OAE-2 coincided with increased pCO2, in line with a volcanic trigger for this event, the observed cooling within OAE-2 probably resulted from CO2 sequestration in black shales outcompeting CO2 input into the atmosphere. Together these results show that the ice-free Cretaceous world was sensitive to changes in pCO2 related to perturbations of the global carbon cycle.
Interactive comment on "Latitudinal differences in the amplitude of the OAE-2 carbon isotopic excursion: pCO2 and paleoproductivity" by E. C. van Bentum et al.
Elisabeth C. van Bentum
Jacobus S. Sinninghe Damsté
- Reaction to C2676–C2678 S. Voigt (Referee)
First records of the grasshopper Machaerocera mexicana Saussure, 1859 (Orthoptera: Acrididae) from the United States and Sonora, Mexico
Robert A. Behrstock
Patrick H. Sullivan
- The grasshopper Machaerocera mexicana Saussure (Orthoptera: Acrididae) is added to the orthopteran faunas of the United States and Sonora, Mexico. Notes are presented on habitat and seasonality.
A New Genus and Species of North American Robsonomyiini (Diptera: Sciaroidea: Keroplatidae: Macrocerinae) from the Florida Keys
Edward I. Coher
- A second genus and species of Nearctic keroplatid fungus gnats (Diptera: Sciaroidea: Keroplatidae: Macrocerinae) attributed to the tribe Robsonomyiini is described: Calusamyia hribari Coher, n. gen., n. sp.. The relationship of this fly from the Florida Keys with Asian genera and species and the single Nearctic described form of the robsonomyiines is briefly discussed.
Two new Neotropical species of Telephanus Erichson near T. serratus Nevermann (Coleoptera: Silvanidae)
Michael C. Thomas
- The Mesoamerican species of Telephanus distinguished by the presence eight lateral pronotal spines
and long temples are reviewed. The group includes T. serratus Nevermann and two previously undescribed species
that are described herein: T. bellus Thomas, new species, from Costa Rica, and the flightless T. monstrosus
Thomas, new species, from Mexico.
The Milliped order Glomeridesmida (Diplopoda: Pentazonia: Limacomorpha) in Oceania, the East Indies, and southeastern Asia; first records from Palau, the Philippines, Vanuatu, New Britain, the Island of New Guinea, Cambodia, Thailand, and Borneo and Sulawesi, Indonesia
Rowland M. Shelley
- The taxonomically neglected milliped order Glomeridesmida and family Glomeridesmidae (infraclass
Pentazonia, superorder Limacomorpha) inhabit 21, rather than seven, regions of the world, being newly recorded
from Thailand; Cambodia; the Republics of Palau, the Philippines, and Vanuatu; New Britain, Bismarck Archipelago;
the Island of New Guinea (both West Papua [formerly Irian Jaya], Indonesia, and Papua New Guinea);
and Sulawesi and Borneo, Indonesia. Occurrence in Fiji is confirmed with two additional samples, and discovery is
predicted in southern China, Myanmar, and perhaps Madagascar. Coupled with published localities, these records
suggest subcontinuous (super)ordinal and familial ranges extending some 12,480 km (7,800 mi) southeastward from
northwestern Thailand to Fiji. Though infrequently encountered, the taxa may actually be diverse and abundant
within this area, which encompasses all of the Indochina and Malay peninsulas, the Philippines, Palau, the Island
of Borneo and Indonesia, Papua New Guinea, the Solomon and Santa Cruz Islands, Vanuatu, and Fiji; it excludes
Taiwan, Australia, New Caledonia, and the Loyalty Islands. The paucity of preserved individuals probably results
from their dark pigmentations and minute sizes, adults being <6.5 mm long; Berlese extractions and sieved litter
techniques are recommended over hand collecting. Glomeridesmida are much more continuous, widespread, and
abundant in the “east” than previously believed and clearly do not comprise a minor, insignificant taxon. The first
glomeridesmidan photos are published.
Two new species of Chrysina Kirby (Coleoptera: Scarabaeidae: Rutelinae) from Mexico
José Monzón Sierra
Jesús García Morales
- Two new species of Chrysina Kirby (Coleoptera: Scarabaeidae: Rutelinae) are described: Chrysina blackalleri from the State of Oaxaca and Chrysina donthomasi from the state of Nuevo León in Mexico.
Distribution of the American milliped genus Boraria Chamberlin, 1943: Introductions of B. stricta (Brölemann, 1896) in New York and B. infesta (Chamberlin, 1918) in Connecticut; indigenous occurrence of B. profuga (Causey, 1955) in Louisiana (Diplopoda: Polydesmida: Xystodesmidae).
Rowland M. Shelley
Chris T. McAllister
Christopher M. Nagy
Mark E. Weckel
Roderick G. Christie
- The southern Appalachian millipeds Boraria stricta (Brölemann, 1896) and B. infesta (Chamberlin,
1918) (Diplopoda: Polydesmida: Xystodesmidae) have become established in Westchester Co., New York, and
Hartford Co., Connecticut, respectively. Only three individuals are available for the latter, but B. stricta has
established a reproducing population in southern New York state. This species is also recorded from Bland Co.,
Virginia, in the Ridge and Valley Physiographic Province. Boraria profuga (Causey, 1955) comprises two allopatric
populations, one in Montgomery Co., Arkansas, and the other in Ouachita Parish, Louisiana. Distributional records
and gonopod drawings are presented for these species plus B. deturkiana (Causey, 1942).
Three new species of Phylocentropus Banks (Trichoptera: Dipseudopsidae) from Vietnam
Tatiana I. Arefina-Armitage
Brian J. Armitage
- Of the 9 known species of Phylocentropus Banks (Trichoptera: Dipseudopsidae), 5 are found in
eastern North America, 1 in Japan, and 3 in Southeast Asia. Three new species of this genus: Ph. tohoku, Ph.
ngoclinh, and Ph. anas from Vietnam are described and illustrated herein. Previously, only 1 species, Ph.
vietnamellus Mey 1995, was known from this country.
New taxa and combinations in Onciderini Thomson, 1860 (Coleoptera: Cerambycidae: Lamiinae)
Eugenio H. Nearns
Ian P. Swift
- Monneoncideres, a new genus of Onciderini Thomson, 1860 (Coleoptera: Cerambycidae: Lamiinae) is
described and illustrated. Six new species of Onciderini are also described and illustrated: Hesycha tavakiliani
from Brazil; Lesbates milleri from Venezuela; Monneoncideres cristata from Ecuador and Peru; Neodillonia waltersi
from Ecuador; Tibiosioma martinsi from Ecuador; and Trestonia wappesi from Panama. Keys to the known species
of Lesbates Dillon and Dillon, 1945 and Tibiosioma Martins and Galilleo, 1990 are provided. The genus
Ophthalmocydrus Aurivillius, 1925 (Onciderini) is transferred to Pteropliini (Lamiinae); and Xylomimus Bates,
1865 (Apomecynini) is transferred to Onciderini. The following new synonymies are proposed: Kuauna Martins
and Galileo, 2009 = Opthalmocydrus Aurivillius, 1925; Kuauna schmidi Martins and Galileo, 2009 = Ophthalmocydrus
semiorbifer Aurivillius, 1925; Paraplerodia Martins and Galileo, 2010 = Tibiosioma Martins and Galileo, 2007;
Paraplerodia acarinata Martins and Galileo, 2010 = Tibiosioma maculosa Martins and Galileo, 2007; and
Ischiomaeocles Franz, 1954 = Lochmaeocles Bates, 1880. The following new combination is proposed: Lochmaeocles
salvadorensis (Franz, 1954), transferred from Ischiomaeocles. The following 37 new country records are reported:
Alexera barii (Jekel, 1861) (Bolivia, Ecuador); Bacuris sexvittatus (Bates, 1865) (Panama); Cacostola brasiliensis
Thomson, 1868 (Argentina); Cherentes niveilateris (Thomson, 1868) (French Guiana); Cicatrodea monima Dillon
and Dillon, 1946 (Ecuador); Clavidesmus metallicus (Thomson, 1868) (Ecuador, Peru); Cydros leucurus Pascoe, 1866
(Brazil); Ecthoea quadricornis (Olivier, 1792) (Ecuador); Eudesmus grisescens Audinet-Serville, 1835 (Ecuador,
Trinidad and Tobago, Venezuela); Euthima variegata (Aurivillius, 1921) (Ecuador); Hesychotypa heraldica (Bates,
1872) (Belize, Guatemala); Hesychotypa punctata Martins, 1979 (Peru); Lochmaeocles basalis Dillon and Dillon,
1946 (Ecuador, Trinidad and Tobago); Lochmaeocles zonatus Dillon and Dillon, 1946 (Venezuela); Lydipta conspersa
(Aurivillius, 1922) (Peru); Neocherentes dilloniorum Tippmann, 1960 (Brazil); Neolampedusa obliquator (Fabricius,
1801) (Ecuador); Peritrox perbra Dillon and Dillon, 1945 (Ecuador); Priscatoides tatila Dillon and Dillon, 1945
(Bolivia); Strioderes peruanus Giorgi, 2001 (Brazil); Trachysomus apipunga Martins and Galileo, 2008 (Peru);
Trachysomus camelus Buquet, 1852 (Venezuela); Trachysomus peregrinus Thomson, 1858 (Ecuador); Trachysomus
thomsoni Aurivillius, 1923 (Venezuela); Trestoncideres laterialba Martins and Galileo, 1990 (Brazil); Trestonia
exotica Galileo and Martins, 1990 (Ecuador); Trestonia fulgurata Buquet, 1859 (Grenada, Trinidad and Tobago);
Tritania dilloni Chalumeau, 1990 (Venezuela); Tulcus paganus (Pascoe, 1859) (Ecuador); Xylomimus baculus Bates,
1865 (French Guiana). Theobroma cacao Linnaeus (Sterculiaceae) is recorded as a new host plant record for Eudesmus